defense secretary leon panetta says the u.s. will help france with intelligence and airlift support. >>> in beijing, the thick blanket of haze is forcing the chinese government to be unusually candid. the most severe air pollution on record is expected to last another day or longer. millions of people are wearing masks or staying indoors. abc's gloria riviera is there. >> reporter: the sun was shining in beijing, but you wouldn't know it. just being outside can make eyes itch and throats burn. this would be my lung tweeted one chinese resident. and time lapse photos showed how chemical clouds made buildings disappear. zero wind, freezing temperatures and factories going full tilt made this week a perfect storm for pollution. at its peak, pollution hit 755 in beijing, making breathing extremely hazardous. by comparison, the worst polluted city in the u.s., bakersfield, california, hit a high of 159 last year. it's super toxic air. >> particle pollution like that can cause heart attacks and strokes that can kill people. it's letha